Health and Environment

Hazards

Inhaling ethylene oxide can cause nausea, vomiting, and neurological disorders. At concentrations of 800 parts per million (ppm), ethylene oxide can be lethal.

Contact with ethylene oxide in solution can cause severe irritation and burns of the eyes, skin, and lungs.

Ethylene oxide is an extremely flammable and reactive gas or liquid. Even static can cause ethylene oxide to ignite.

Chronic (Long-Term) Health Effects

Ethylene oxide is a known or probable human carcinogen, depending on the classifying body. The National Toxicology Program recently upgraded it to a known human carcinogen. The U.S. Environmental Protection Agency (EPA) classifies it as a Group B1 (probable) carcinogen and the International Agency for Research on Cancer (IARC) classifies it as a Group 2A (probable) carcinogen.

The degradation products of ethylene oxide-based nonylphenol ethoxylates, nonylphenol and shortchained nonylphenol ethoxylates, are acutely toxic to marine organisms and have the potential to bioaccumulate.

Exposure Routes

Use ethylene oxide in closed systems. If a closed production system is infeasible, enclose operations and use local exhaust ventilation. If ethylene oxide exposure may exceed 0.1 ppm, use a Mine Safety and Health Administration/National Institute for Occupational Safety and Health-approved supplied-air respirator with a full facepiece.